Digestive System And Enzymes Flashcards
What is digestion?
Digestion is the breaking down of large, insoluble molecules of food into smaller, soluble molecules
This is so they can be absorbed into the bloodstream
What is physical/mechanical digestion?
It is the first stage of digestion
Where large chunks of food or broken into smaller bits, firstly by chewing
It’s speed up chemical digestions as the food will have a larger surface area
It is necessary so we can swallow the food
What is chemical digestion?
The second stage of Digestion
It is slower than physical as large molecules are chemically broken into smaller ones
It is done by enzymes
How does saliva help digest food
It contains AMYLASE - digests starch into sugar
Contains MUCAS - a slimy Substance which helps food slip down the throat
What is peristalsis?
It is when the circular muscles in the gullet/oesophagus’ wall contract and squeeze behind the food and the muscles in the front relax to help it along
What is the stomach?
A muscular bag that can hold 2 L of food.
The muscles turn the food to mix it with the digestive juices
What do the digestive juices that the stomach produced contain?
PROTEASE - Starts digestion of protein into amino acid’s
HYDROCHLORIC ACID - makes conditions perfect for protease to work. Protease works best in acidic pHs
What is the function of the liver?
It produces bile
What is the function of the gallbladder?
It is where bile is stored
What is the function of the bile duct?
To release pile into the intestine
What is the function of the pancreas?
To make pancreatic juices
What happens in the large intestine ?
Food is passed along and water is absorbed
What does the salivary gland do?
It PRODUCES SALIVA - Moistens food to form a ball to swallow. Contains enzymes to digests food
What does the oesophagus do?
It passes food down to your stomach
Its walls are made of smooth-muscle back on contract
What is the function of the stomach?
To mix interned food by contracting its walls
To kill pathogens in the food and provide a low pH for enzymes should I just protein by producing hydrochloric acid
How is the stomach adapted for its function?
It makes digestive juices
It is made of muscle
It can withstand acids
What does the small intestine do?
It adds bile and digestive juices to the liquid that is squeezed gently along
It has a large surface area with villi and microvilli
What is the purpose of stomach acid?
It chemically digests food (especially protein)
Kills pathogens
What is the function of bile?
It emulsifies fats - this means itTurns fat into smaller droplets so they have a bigger surface area for enzymes to work on to make the process quicker
What is emulsification of fats?
When facts are turned into smaller droplets
What is a villus?
I think I like projection that increases the surface area of the small intestine
What are enzymes?
Proteins
Biological catalysts - speed up chemical reactions in the body and not used up
Specific to one chemical reaction (complementary)
Where is bile produced?
The liver
Where is bile stored?
The gall bladder
